1. Field of the Invention
Aspects of the present invention relate to a flat panel display device, and more particularly to a flat panel display device capable of reducing a resistance difference arising from a difference in the lengths of signal lines and to a design of the signal lines arranged in edges of wire groups diverging from a driving circuit unit to have a stable resistance value.
2. Description of the Related Art
In recent years, there have been many attempts to develop various flat panel display devices capable of reducing weight and volume associated with a cathode ray tube, because weight and volume are problems of the cathode ray tube. The various different flat panel display devices include a liquid crystal display device, a field emission display device, a plasma display panel device, an organic light emitting display device, and other devices.
Among the various different types of flat panel display devices, the liquid crystal display device displays an image by controlling a transmission of light that is generated from an external backlight. The liquid crystal display device may display a large-area (or large-sized) image in high resolution through development of state-of-the-art display techniques. Therefore, the liquid crystal display device may be widely used in various fields.
On the other hand, the organic light emitting display device displays an image by using an organic light emitting diode that generates light by an apparatus/method of recombining electrons and holes. The organic light emitting display device has come into the spotlight as a next-generation display device since the organic light emitting display has advantages such as a rapid response time and is able to be driven to have low power consumption.
The liquid crystal display device and the organic light emitting display device include a display unit having pixels arranged in intersecting regions of scan lines and data lines and a driving circuit unit having a scan driver to supply a scan signal to the scan lines and a data driver to supply a data signal to the data lines.
In the various flat panel displays, the driving circuit unit is arranged in an edge region of a display panel having a display unit formed therein or a flexible printed circuit board connected with the display panel, for example. The driving circuit unit is connected to ends of the signal lines such as the scan lines and the data lines.
For the connection, the ends of the signal lines to be coupled to the driving circuit unit are crowded into a narrow region. On the other hand, the ends of the signal lines that are connected to the pixels are arranged at predetermined distances or intervals according to the size of the pixels of the display unit, and are therefore formed at wider distances than the ends of the signal lines that are coupled to the driving circuit unit. Accordingly, the distances between the signal lines are gradually widened like ribs of a fan in a region between the driving circuit unit and the display unit, or some of the signal lines form wire groups in regions where the signal lines diverge (hereinafter, referred to as divergence regions).
The arrangement of the signal lines in the divergence regions is such that the signal lines arranged in a central region of the divergence region extend nearly straight without a change in direction, but the signal lines near edges of the divergence region are increasingly bent at an angle as the signal lines approach the edges of the divergence region. Accordingly, the lengths of the signal lines are different depending upon a location within the divergence region, and a resistance value of each of the signal lines is varied. The difference in resistance values results in deterioration of picture quality in the flat panel display devices.
Particularly, in the case of the liquid crystal display device and the organic light emitting display device using a voltage control system to adjust and control a voltage applied to each of the pixels, the pixels receiving the same data signal will emit light with different luminances due to the resistance difference in the signal lines. The resistance difference will result in a deterioration of quality in the pictures due to a lack of precise voltage control.